On the 5th July, 1923, the 4.27 p.m. train from Brighton was travelling towards Barcombe Mills on the up road, it was almost completely derailed, the engine being overturned to the right, foul of the down road. Of the four coaches comprising the train, three of which were boogie passenger vehicles, and the other a covered carriage truck (six wheeled) marshalled third from the engine, the first of three were derailed all wheels. In the case of the fourth and last coach, the wheels of the leading boogie were derailed, the remainder keeping the track. The distance between the first point of derailment and the leading wheels of the engine after the train came to rest was 69 yards.

As a result of the accident, the driver of the train was injured and the guard suffered from shock. no complaints of injury were made at the time by the passengers, but one compliant of shock was received subsequently to the accident.

The damage to the engine was not serious, and comprised mainly torn and bent footsteps, and damage to the right hand tank, etc., caused by the engine overturning. The three leading vehicles of the coaching stock were somewhat considerably damages, and four side springs were broken of the fourth vehicle.

The train was drawn by side tank engine 253, 0-4-2 type, running bunker first, and weighing in working order 43 1/2 tons. the total weight of the train, excluding engine, was 79 1/4 tons, and it was fitted throughout with the Westinghouse automatic brake.

The weather was at the time hot and sunny.

Description

The railway between Culver Junction and Barcombe Mills, a distance of 39 chains, consists of a double line of road running approximately from south-west to north-east from Culver Junction to Barcombe Mills in the up direction. The derailment occurred about midway between the junction and the station.

The up road was laid during the first half of 1904 with 95Ib. material a few pattern material. The down road was relaid with second-hand 95Ib. material a few weeks before the accident. The rails are 30 feet lengths carried in chairs weighing 46lbs., which are secured to sleepers of the normal dimensions by two spikes and two trenails each. The keys on the up road are either of teak or oak, in the proportion of about three to one. These keys are straight, and for most part of uncompressed material. The joints are secured to fishplates 1 foot 7 inches long, with spacing of 6 inches between the two insides bolt holes, the fishing angle being 20 degrees. The fish bolts are of the snap-headed type, having a total length over the head of 5 1/2 inches and a diameter of 15/16 inch. Plain nuts 1 1/4 inches deep, without washers,are used.

The ballast at the time was of shingle, and the formation of the line is on low embankment, the gradient being level for about half a mile south of Barcombe Mills.

Conclusion

The train concerned in this case was booked to run from Brighton to Tunbridge Wells, calling at all station. It is timed to leave Lewes at 4.49 and to arrive at Barcombe Mills at 4.58, passing Culver Junction at 4.56. This timing implies an average speed of 32.37 miles an hour between Lewes and Culver Junction, and 14.62 miles an hour between the Junction and Barcombe Mills. On the afternoon in question the train was running slightly ahead of the service timing, and passed Culver Junction at about 4.55, having occupied approximately the time allowed on the run from Lewes. The evidence of the signalman at Culver was that the train passed his post at the normal rate of speed. Henry Rogers, the driver, stated that he shut of steam as usual just before reaching the Junction he made a slight brake application by reducing his air pressure a few pounds. Very shortly afterwards, he noticed the up road was distorted just ahead of him in a more or less S-shaped form. The train was then travelling at an estimated speed of 20 miles an hour, and Rogers at once made a full brake application, the derailment occurring immediately afterwards. The distortion of the road was also observed by Roger’s fireman, Firth.

The foregoing is the only direct evidence available as to the cause of this derailment. There was no indication of anything amiss with the engine wheels, which were found true to gauge. The tyres were good, those fitted to the trailing wheels, which were leading at the time, having only been turned a few days previously. There was no indication of any obstruction on the road, either from the subsequent condition of the permanent way or of the stock. After the derailment, the up road was found distorted for a distance of approximately 34 yards on the approach side of the point (11 miles 588yards from Brigton) where the derailment commenced. This distortion was of a sinuous character, being slightly to the right for the first 6 yards, i.e., from 11 miles 554 yards to 11 miles 560 yards, pronouncedly to the left for the next 27 yards, and thereafter to the right again. From about 11 miles 595 yards the up road was completely destroyed as a result of the derailment.

The evidence of the Enginemen, taken in conjunction with the complete absence of any indication to suggest an alternative cause, leads to the conclusion that this derailment resulted from server distortion of the road, which took place at some moment prior to the arrival of the train. There is sufficient evidence to show that the interval of time between the distortion of the road and the arrival of the train must have been short, and may quite probably have been almost momentary. The roadway certainly in order for the previous train, the 2.52 p.m. from Brighton, which passed over the line at about 3.30. the length ganger, Henry Skinner, who had been over the section where the derailment eventually took place very shortly before the arrival of the train. There was no sign of any disturbance.

All the circumstances of the case point to the distortion of the road having been primarily due to the high temperature reached on the afternoon in question, the maximum sun and shade temperatures registered at Kew being 130 degrees and 84 degrees respectively, the maximum shade temperature being reached at 6.55 p.m. It is probable that several causes contributed to the fact that distortion resulted from the considerable expansion so set up. It appears from the evidence of Charles Allen, who was in charge of a relaying gang at work on this section, that on the 2nd and 3rd of the month the top layer of ballast had been reeked off a length of the up road as a preliminary to re-surfacing with flint in place of the old shingle ballast. This was part of a general programme in this district of a similar character. Allen’s gang was during this period actually engaged in relaying the down road at Barcombe Mills Station. On the 2nd and 3rd of the month, however, they were awaiting certain materials required for the relaying work, and therefore the time of the gang was, on the Permanent Way Inspector’s instructions, occupied in the manner described above, which accounted for the fact that the new ballast had not been filled in on the day of the accident. The length on which this boxing had been removed was from 11 miles 560 yards to 11 1/2 mile, its commencement therefore coinciding within a few yards with the place where the distortion of the road was first apparent after the accident. Ganger Allen explained that only the loose surface was raked off, leaving the existing bed in position about 2 inches above the bottom of the sleepers. Length ganger Skinner was, of course, aware that this ballast had been raked off, and confirmed Allen’s evidence as to the extent of its removal. He gave it as his opinion that e did not consider that the road had been in any way rendered unsafe for traffic. Had this been the case, he would at once have drawn attention to the fact.

Skinner walked his length, the south boundary of which is the 11 1/4 mile post, twice on the day in question, starting on the first occasion at 7.40 a.m. and on the second occasion at 2.30 p.m., as already mentioned. On the first occasion, with the exception of two or three keys which had fallen out and which he refixed, he found nothing which required attention. He looked particularly, as he always does in hot weather, at the expansion joints and found none of them closed up. He noticed, as he walked, the characteristic sound of the joints moving under the expansion of the rails, the morning being bright and sunny. On his afternoon inspection, he found the conditions much the as they were in the morning, except that all keys were in position and only a few required tightening. Skinner’s general conclusion was that the road was in thoroughly satisfactory order. In regard to the special precautions prescribed for hot weather conditions, Skinner said that, following upon the annual reminder issued in May, the whole of the bolts on his length were eased during that month. He had again gone through the bolts on his length a few days before the derailment, and did not on this occasion find that any of them requires slackening. Skinner added that as a rough indication the nuts were adjusted so that they could be moved by one hand with a spanner. There were at the time no instructions with regard to greasing fishplates on his section.

Mr. Wilcox, the Assistant District Engineer, who was on the scene of the accident about one hour and a quarter before it occurred, and saw the priding train pass over the up line, confirmed the ganger’s evidence that the road was in good condition. After the accident, he proceeded at once to the spot, and cam,e to the conclusion that derailment was du to buckling. He tried some of the nuts near the scene of the accident and found that he could move them with a spanner with one hand, and considered them in a satisfactory condition. Mr. Brown, the District Engineer, who was on the scene of the derailment at about 7 p.m., also thoroughly examined the road and found that the joints between Culver Junction and the scene of the derailment were quite satisfactorily open, and that the nuts were sufficiently slacked. The road on the south side of the derailment was tested for gauge immediately after the accident and found to be from 1/16 inch to 1/8 inch tight to gauge.

On the day of the Inquiry, the road had of course, been relined and relaid as necessary, and there was therefore nothing to be learnt from the section on which the derailment had actually taken place. I examined the road adjacent to this section, on which I was assured that no renewal work had meantime been done, and found it in thoroughly good order. Chair fastenings and key were sound and secured and joints were properly spaced. There was no indication of any creep, and it appears that very little trouble had been experienced on this account. Ganger Skinner said that during the whole of the 19 years since this road was laid, it has only been drawn back twice, the last occasion being some two yeas ago.

My general conclusion is that the buckling was mainly due to excessive friction at certain of the joints, which caused sufficient compression in the rails to result in their distortion. Both Mr. Brown and Mr. Wilcox were of the same opinion, and thought that the excessive friction was probably due to some of the joints having been a little rusted up. No doubt the removal of the upper layer of ballast was a contributory and in my opinion a material factor in the result, since the lateral resistance of buckling, particularly with ballast of this character, must have been appreciably reduced. It is, I think, very probable that the final factor was the vibration of the train, and that as the evidence suggests, buckling only took place immediately before its arrival on the section of road concerned.

I do not consider that responsibility for the accident rests upon any of the men concerned. On the contrary, the circumstances show that proper attention was given by them their various duties. Driver Rogers and his Fireman appear to have been carefully observing their road, and there can be little doubt that they saw the buckling almost, if not quite, as soon as it actually took place. Ganger Skinner was evidently fully alive to the importance of th special inspection duties necessitated by hot weather conditions, and I am satisfied that he omitted no precaution within the terms of his instructions. The section of road as a whole appears to be particularly well maintained. So far as the removal of the top layer of boxing is concerned, I can see nothing in gangers Allen’s action which was either unusual or in itself risky, having regard to the character of the permanent way and the nature of the traffic on the branch. In Allen’s opinion, the question of risk in this respect is mainly one of speed, and on a branch such as this, where speeds are always low, he would not consider it necessary to put out warning boards as he would do on an express line.

This case emphasises the necessity for sufficient freedom of movement at rail joints to enable the rails to expand without undue compressive strain. It is common and I think sound practice to encourage this movement by the use of great or its equivalent between rail and fishplate. This obviates any risk of rusting up of the joints and undue friction between the fishing angle of the plate and rail, which, with untreated joints, may result even where bolts are not unduly tight. I understand that instructions have recently been issued for greasing of fishplates to be carried out in hot weather conditions throughout the whole of the Southern Railway.